Tirzepatide

What is Tirzepatide

Tirzepatide is a novel dual agonist of the GLP-1 receptor and GIP receptor, primarily used for the treatment of type 2 diabetes. It offers dual benefits of blood glucose control and weight management. By activating intestinal hormone receptors, it regulates insulin secretion, delays gastric emptying, and suppresses appetite to achieve glycemic control and weight management.

Mechanism of Action of Tirzepatide

Tirzepatide mimics the action of natural human hormones to enhance insulin secretion, inhibit glucagon release, delay gastric emptying, and suppress appetite, thereby achieving blood glucose lowering and weight reduction effects. Its dual-target mechanism provides superior blood glucose control and weight loss efficacy compared to single-target drugs.

Tirzepatide Indications and Usage

Diabetes: Approved by the FDA in May 2022 for improving glycemic control in adults with type 2 diabetes. China has also approved the same indication.
Obesity Management: Approved by the FDA in November 2023 for obesity (BMI ≥ 30 or overweight with complications). Currently undergoing marketing approval procedures in China.
Obstructive Sleep Apnea: Approved by the FDA in 2024 to improve OSA symptoms in obese patients, becoming the world’s first dual receptor agonist for this indication.

Tirzepatide Dosage and Administration

Administered as a weekly subcutaneous injection. Initial dose: 2.5mg, which may be gradually increased to 5mg, 7.5mg, 10mg, 12.5mg, or 15mg. Store refrigerated at 2°C to 8°C. Recommended injection sites include the abdomen, thigh, or outer upper arm; rotate injection sites to minimize discomfort.

Common Side Effects and Precautions for Tirzepatide

1. Gastrointestinal Reactions
Includes nausea, diarrhea, vomiting, etc., commonly occurring early in treatment and gradually diminishing with prolonged use. Initiate at a low dose and increase gradually.
2. Risk of Hypoglycemia
Combination with insulin or sulfonylureas may increase hypoglycemia risk. Closely monitor blood glucose and adjust co-administered drug doses.
3. Other Potential Risks
• Thyroid C-cell tumors: Animal studies suggest potential increased risk. Contraindicated in patients with personal or family history of medullary thyroid carcinoma (MTC).
• Pancreatitis: Seek immediate medical attention for persistent abdominal pain.
• Allergic reactions: Rare but requires vigilance.

Clinical Efficacy of Tirzepatide

In Phase III clinical trials, tirzepatide demonstrated:
• An average blood glucose reduction 1.6 percentage points greater than placebo in diabetic patients;
• Weight loss ranging from 18.3% (in MC4R mutation carriers) to 43.5 pounds (in the highest dose group) over 72 weeks in obese patients;
• A 47% greater weight loss effect compared to semaglutide.